Jon Cryer Was 'Blissfully Unaware' Demi Moore Was Struggling with Addiction While Dating Her in '80s (Exclusive)

The two starred together in 1984's 'No Small Affair'

Jon Cryer is reflecting on his brief relationship with former costar Demi Moore.

The actor starred in No Small Affair alongside Moore in 1984 before either of the two were well known, and art began to imitate life as they briefly dated while making the film.

“We dated for a short time while we were working on No Small Affair, but I guess our particular affair was, in fact, pretty small,” says Cryer, 59, who is featured in the new documentary BRATS, directed by Andrew McCarthy and streaming on Hulu June 13.

“She was already struggling with a drug problem. One that I was blissfully unaware of until a couple of weeks before the movie ended," he adds.

Related: Brat Pack Babies, Husbands and Wives: Meet the Families of the A-list '80s Favorites

In the 1980s, Moore, now 61, went to rehab for drug and alcohol addiction. Then, after remaining sober for more than 20 years, she relapsed in 2012, eventually going back to rehab for addiction as well as an eating disorder, sources told PEOPLE at the time.

Still, even as early as the '80s, Cryer knew Moore had that unmistakable spark despite her private troubles.

Related: The Brat Pack: Where Are They Now?

“What would always be great about her was already evident; that incredible combination of vulnerability, toughness and beauty,” he says.

While Moore famously became a member of the Brat Pack, Cryer always considered himself more adjacently related to the group.

“I didn’t perceive myself as part of the 'Brat Pack' because I didn’t think I was one of the cool kids. And they were definitely the cool kids,” he says. “I thought the two films that defined the group were The Breakfast Club and St. Elmo’s Fire, neither of which was I in.”

Moore, on the other hand, joined the crew of up-and-coming teen stars when she appeared in St. Elmo's Fire in 1985 — just a year after her role with Cryer in No Small Affair.

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“She was incredibly charismatic and had a much better grasp of the business than I did," the actor admits. "She knew everyone in town, but we were both really nervous about being leads in a movie for the first time."

Moore would also go on to star in Ghost (1990), A Few Good Men (1992) and Indecent Proposal (1993), among other cult favorites, while Cryer took on the role of Duckie in Pretty in Pink (1986) alongside Molly Ringwald.

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If you or someone you know is struggling with substance abuse, please contact the SAMHSA helpline at 1-800-662-HELP.

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